Simultaneous ultraviolet-ultrasound (UV-US) assisted synthesis of silver nanoparticles (AgNPs) using microwave-assisted extract of unripe balimbing (Averrhoa carambola L.) fruit as reducing agent for the photocatalytic degradation of ibupropen

ABSTRACT: Simultaneous ultraviolet ultrasound assisted synthesis is a novel technique that maximizes the combinatory effect if the fast synthesis time of sonochemical synthesis and the cost-effective photochemical synthesis to facilitate the fast and cost-effective reduction of silver ions (Ag+) into AgNPs from microwave assisted unripe Balimbing Fruit extract. The mechanism by which the simultaneous synthesis works is that ultraviolet provides the necessary energy to excite the silver ions and initiate the synthesis process while simultaneously generating acoustic cavitation through the sonication localizing high temperature and pressure needed to reduce the silver ions into AgNPs. The study investigated the effect of the combination of varying ultrasound power (100W, 150W, and 200W) and ultraviolet exposure time (20mins, and 60 mins) to the yield of AgNPs. A combination of 100W of ultrasonic power and 60 mins of ultraviolet exposure time produced the highest yield of 0.2239g/100 mL AgNO3-Balimbing solution. The yield of the simultaneous synthesis is almost 2x higher than that of the controls, ultraviolet assisted synthesis (0.1412g/100mL solution) and ultrasound assisted synthesis (no yield). Characterization techniques were employed to verify the existence of silver nanoparticles. The peak absorbance of 0.75 at 440nm showed by the Ultraviolet-Visible spectroscopy and the result of 45.4386% of silver on the Xray-Fluorescence, verified that the synthesized particle is needed silver nanoparticles. Field Emission Scanning Electron Microscopy (FESEM) proved that the synthesized particles is on the nano-regime with non-uniform size distribution between 21-72 nm, which is a characteristics of AgNPs synthesized through sonication. Ibuprofen, the world’s third most consumable drug and Philippines second most used over-the counter NSAIDs, undergone 22.61% photocatalytic degradation after 60 minutes of exposure to AgNPs which opens future opportunities for the utilization of the AGNPs for photocatalytic degradation of emerging pollutants.

Filipiniana